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INTRODUCTION
Welcome to the Don Theorem Prover (DTP), version 2.4
DTP is an inference engine for first-order predicate calculus, and it
specializes in domain-independent control of reasoning.
Please send comments to Don Geddis at
Geddis@CS.Stanford.EDU
or
Computer Science Department
Stanford University
Stanford, California 94305
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IMPLEMENTATION
The code was developed under
Franz Allegro CL 4.2.beta.0 (on a Sun Sparc)
and is written in Common Lisp with some CLtL2 extensions (e.g. the LOOP macro).
Earlier versions were tested under
Lucid HP Common Lisp Rev. A.04.01 (on an HP-9000 Series 300/400)
MCL 2.0p2 (on an Apple Macintosh)
although the latest version has not been.
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AVAILABILITY
DTP is available on the World Wide Web (WWW) from
http://meta.stanford.edu/FTP/dtp/
or by anonymous FTP from
meta.stanford.edu:/pub/dtp/
with the files
dtp.tar.Z Common Lisp (CLtL2) source code
logic.tar.Z Logic puzzle examples
manual.ps Documentation
Unfortunately, the documentation is out of date by some number of versions.
Most of the functionality is shown in the examples in the logical theories,
which are exercised by running the function (test-dtp). Other new functions
of interest include (settings), to examine the state of the theorem prover
options, and (show ), which takes a proof object or answer object
and generates a postscript graph of the space using AT&T's program "dot".
Also of interest may be some technical papers, available as
http://meta.stanford.edu/FTP/papers/ [WWW]
meta.stanford.edu:/pub/papers/ [FTP]
including
overview.ps An overview of first-order inference
caching.ps Subgoal caching in first-order inference
complete.ps Completeness of caching in first-order inference
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VERSION
Version history:
1.0 Resolution-based inference system
2.0 Subgoaling inference system
2.1 Corrected reduction inference combined with caching
2.2 Depth limits and iteration (broken)
2.3 Reduction check at conjunct instead of subgoal
2.4 General "view" tool on proofs and answers
Note: This is an alpha release, pending the resolution of current theoretical
questions about completeness of postponement caching.
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